Conventional Treatment of Heart Failure
The 2013 Guideline for the Management of Heart Failure issued by the American College of Cardiology Foundation and American Heart Association (ACCF/AHA) was updated in 2017 to reflect the most recent evidence (Yancy 2013; Yancy 2017). The guideline is intended to be used in the context of best clinical judgement to improve quality of care and meet the needs of the majority of heart failure patients under most, but not all, circumstances. Recommendations in the guidelines address clinical evaluation and diagnosis, prevention, and treatment and management, and are stratified by disease severity.
Treatment Considerations for Patients at Risk for Heart Failure (ACCF/AHA stage A or B)
Patients with stage A heart failure have no symptoms of heart failure and no structural problems in their heart, but are at high risk of heart failure due to the presence of cardiometabolic conditions like high blood pressure, unhealthy blood lipids, diabetes, or obesity. Stage B heart failure, on the other hand, is defined as structural changes to the heart muscle from a previous history of heart attack or other blood supply blockage, but without signs or symptoms of heart failure. The guideline acknowledges a role for self-care and related education, and exercise or physical activity for those who are able. A restriction of dietary sodium to 1500 mg per day is considered to be indicated in most stage A or B heart failure patients. Sleep disorders including sleep apnea are common in heart failure patients, and should be discussed with a health care provider (Yancy 2013).
Medications. The recommended medications for stages A and B heart failure are:
- Angiotensin-converting enzyme (ACE) inhibitors. ACE inhibitors restrict the activity of ACE, reducing the synthesis of the hypertensive hormone angiotensin II. Enalapril (Vasotec) and lisinopril (Zestril) are examples of commonly prescribed ACE inhibitors (Izzo 2011). By lowering the levels of angiotensin II, these medications promote the dilation of blood vessels (BHS 2008). ACE inhibitors are beneficial in patients with all degrees of symptomatic heart failure, regardless of the presence or absence of coronary artery disease. They reduce death and heart failure-related illness in patients whose heart function is compromised. ACE inhibitors must be used with caution in patients with very low blood pressure, advanced kidney disease, and elevated blood potassium. This class of drugs can cause a type of severe skin swelling called angioedema, and are contraindicated in patients with this condition. Cough is one of the more common side effects of ACE inhibitors. Mainly due to these two side effects, not all patients are able to tolerate this class of medication (McMurray 2016; Yancy 2017).
- Angiotensin receptor blockers (ARBs). ARBs may be prescribed as an alternative to ACE inhibitors, generally in individuals who are unable to tolerate ACE inhibitors due to side effects such as persistent cough or angioedema. ARBs have been demonstrated in randomized controlled trials to reduce death and heart failure-related illness, particularly in patients intolerant of ACE inhibitors. Like ACE inhibitors, ARBs must be used advisedly in patients with low blood potassium, advanced kidney disease, and very low blood pressure. Commonly prescribed examples of ARBs include candesartan (Atacand) and valsartan (Diovan) (Taylor 2011; McMurray 2016; Yancy 2017).
- Beta blockers. Beta blockers lower heart rate and blood pressure by blocking beta-adrenoceptors (AHA 2017b). Beta-adrenoceptors bind adrenaline and norepinephrine (catecholamines), triggering vasoconstriction, increased heart rate, increased heart contraction force, and other changes in cardiovascular tissues. Examples of beta blockers include carvedilol (Coreg), bisoprolol (Zebeta), and metoprolol (Lopressor). These three medications, using the sustained-release version of metoprolol, reduce the risk of death, and are indicated for patients with current or past history of reduced ejection fraction (Fisker 2015; Yancy 2013). In stage B patients, beta blockers are recommended in conjunction with either an ACE inhibitor or ARB in patients who have had a heart attack, or another blood supply blockage and have reduced ejection fraction (Yancy 2013). Side effects associated with beta blockers include weight gain, fatigue, and cold feet or hands; less commonly, depression, shortness of breath, or insomnia may occur. Newer-generation beta blockers are believed to have a more favorable side effect profile (Mayo Clinic 2016; Fisker 2015).
Treatment Considerations for Patients with Heart Failure (ACCF/AHA stage C)
For patients with structural changes to the heart muscle, and past or current heart failure symptoms (stage C), the current guideline recognizes the importance of self-care, patient education, and social support. CPAP treatment for patients with sleep apnea can increase ejection fraction and improve overall status in stage C patients; and exercise training, physical activity, or cardiac rehabilitation also improve overall status in these patients. Pharmacological treatment for this degree of disease uses the same medications as stages A and B (Yancy 2013). Additional medications indicated for treating stage C heart failure are:
- Angiotensin receptor-neprilysin inhibitor (ARNI). Although treatment with an ACE inhibitor or ARB has long been a mainstay of medical therapy for symptomatic heart failure, new guidelines recommend the substitution of an ARNI in place of these drugs in most patients with mild-to-moderate symptomatic heart failure with reduced ejection fraction (Yancy 2017). The first of these drugs to gain FDA approval for use in heart failure treatment combines sacubitril and the ARB valsartan (Entresto) (Kaplinsky 2016). By inhibiting the activity of the enzyme neprilysin, sacubitril prevents the breakdown of natriuretic peptides, thus improving regulation of fluid balance and renal and cardiovascular function (Wong 2017; Yandrapalli 2017). Research shows that, in carefully selected patients, sacubitril/valsartan reduced the risks of cardiovascular death and heart failure-related hospitalizations more than standard therapy with an ACE inhibitor (Kaplinsky 2016). The side effect profile of sacubitril/valsartan is roughly comparable to the ACE inhibitor enalapril, though it is far more expensive (King 2016; Sehn 2017; Marques da Silva 2017).
- Diuretics. Diuretics are used in stage C heart failure patients with reduced ejection fraction to address symptoms of fluid retention. They work by altering the way the kidneys handle sodium or chloride, thus increasing urination. The most commonly employed diuretic in heart failure is furosemide (Lasix), but many others are available including thiazide diuretics and spironolactone (Yancy 2013). Spironolactone reduces testosterone production and activity (Rathnayake 2010).
- Aldosterone antagonists. Stage C patients with mild to complete limitations of the ability to be active, and markedly compromised ejection fraction are prescribed aldosterone receptor antagonists to reduce the risk of cardiac-related illness and death (Yancy 2013). Aldosterone is a hormone produced by the adrenal glands that acts on the kidneys to increase retention of sodium and water. Spironolactone and other aldosterone antagonists inhibit the activity of aldosterone, decreasing fluid retention and diminishing blood volume (Booth 2002).
- Cardiac (digitalis) glycosides. Cardiac glycosides are compounds present in many plants, and are historically derived from the Digitalis (foxglove) genus of plants. They have been used in the treatment of cardiac problems for over 200 years (Kapitanyan 2017). Digoxin (Lanoxin), a medication of this type, is sometimes used in stage C patients with reduced ejection fraction, as it reduces hospitalizations related to heart failure (Yancy 2013). Digoxin toxicity can cause potentially serious heart rhythm irregularities, as well as symptoms including vomiting, headache, and confusion (Ehle 2011).
- Anticoagulants. For patients with chronic heart failure, atrial fibrillation, and any additional stroke risk factor, anticoagulants are used; they are also often prescribed even in the absence of stroke risk factors (Yancy 2013).
- Sinoatrial current inhibitor. Increased resting heart rate is a risk factor for heart failure-related hospitalization and death (Muller-Werdan 2016). Ivabradine (Corlanor), classified as a sinoatrial current inhibitor, has recently been added to the list of medications to consider for treating symptomatic heart failure with reduced ejection fraction, as it has been demonstrated to reduce cardiac hospitalization risk (Yancy 2017). Ivabradine is indicated for those being managed in accordance with treatment guidelines, including the maximum tolerated dose of a beta blocker, and have a resting heart rate of 70 beats per minute or higher (Davis 2016; Yancy 2017). Side effects such as excessively low heart rate and abnormal heart rhythm, as well as high cost, limit its use (Alshammari 2017).
- Medical devices. In selected cases of relatively advanced stage C heart failure with reduced ejection fraction, implantable cardioverter-defibrillator and cardiac resynchronization therapy may be recommended to lower the risk of cardiac-related death (Yancy 2013).
Advanced Heart Failure (ACCF/AHA stage D)
Stage D heart failure, called advanced heart failure or refractory end-stage heart failure, accounts for 5‒10% of heart failure cases. Stage D indicates the condition is not responding to all available guideline-directed treatment; this stage is characterized by severe symptoms, including shortness of breath and fatigue, even at rest or with minimal activity. Although certain aggressive measures such as mechanical circulatory support or heart transplant may be considered, authoritative sources also discuss end of life hospice care and palliative treatment for stage D. Before stage D is diagnosed, all other possible causes and treatable disorders, such as thyroid disorders and pulmonary conditions, must be considered and ruled out (Yancy 2013; Adler 2009; AHA 2017a).